Câu 1: Giá trị của đa thức 2 2 B x xy y = − + 4 2 15 - 8xy - 10 tại x = -2 và y = -1 bằng?
A. 10 B. -9 C. 1 D. 9

The probability that she lives 73 years is 0.1897

Step-by-step explanation:

Here the random variable x= 83  years where x is the average life span of a Hispanic female. the mean would be 41.5 years

We have to find the probability that Dora lives  73 years. Her present age is 53 years.

In mathematics this can be re written as  P(x=73)

Variance= ∑ ( x-x`)/1= 83-41.5/1= 41.5

Standard deviation = √var= √41.5= 6.4 years

At x= 73 we have z= 73-41.5/6.4= 4.92

Using the z tables the value under the area 4.92 = 0.1897

So the Probability that she lives 73 years is 0.1897